1. Technical Field
The present invention relates to a semiconductor device.
2. Related Art
A structure has been proposed in which a concave portion is formed in a substrate and a semiconductor chip is provided in the concave portion in order to reduce the thickness of a package when a plurality of semiconductor chips is formed on the substrate.
Japanese Unexamined Patent Publication No. H10-242380 discloses a semiconductor device in which two elements are accommodated in a concave portion formed in a substrate. In this structure, the two elements are arranged with an angle of 90° therebetween. In addition, the two elements are both connected to the substrate by bonding wires.
In addition, there is a structure in which one semiconductor chip is accommodated in a concave portion of a substrate and is connected to the substrate by a flip-chip technique, and an upper semiconductor chip is connected to the substrate by the bonding wires. In this structure, stitches to which the upper semiconductor chip is connected through the bonding wires are provided around the concave portion of the surface of the substrate. In this case, a lower semiconductor chip connected by the flip-chip technique is fixed to the substrate by an underfill. In addition, the upper semiconductor chip is sealed by a sealing resin and the bonding wires are also covered with the sealing resin.